JP2009067017A - Recording sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording sheet having a superior shelf life with no smears, high pressure sensitive and heat sensitive coloring concentration, superior sensitivity, and formable like a roll, in regard to a recording sheet having recording layer capable of carrying out pressure sensitive recording and heat sensitive recording wherein a layer provided with the recording layer capable of carrying out pressure sensitive recording and heat sensitive recording and another layer further provided with a heat sensitive recording layer are bonded by a pseudo-bonding layer. <P>SOLUTION: The recording sheet is characterized by that it has a first layer provided with both a first base material layer and the recording layer capable of carrying out pressure sensitive recording and heat sensitive recording, and a second layer having at least a second base material layer, and an intermediate layer is provided between a pressure sensitive recording layer and a heat sensitive recording layer of the first layer, and the second layer is laminated on a recording lay of the first layer. The pseudo-bonding layer is formed by a wet laminating method. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a recording sheet having a recording layer capable of pressure sensitive recording and thermal recording.

Pressure-sensitive recording, which is performed by pressurization, is a recording method that can be copied at the same time as recording, and has been used for a long time in receipts and deposits. Thermal recording is employed in facsimiles and various printers because the printing device is compact and relatively inexpensive.
In recent years, as described in, for example, Patent Document 1, a recording sheet having a multilayer structure in which a layer capable of pressure-sensitive recording and another layer such as a heat-sensitive recording layer are superposed has been proposed. In a recording sheet having such a multilayer structure, usually, a method in which only the end portions are partially adhered so that the respective layers are not displaced or separated, sprocket holes are formed at the end portions of the respective layers, In general, a method of fitting a pin of a paper feed roll so as to prevent each layer from shifting is generally adopted.
JP 2004-142141 A

As a method for obtaining a recording sheet capable of simultaneously recording pressure-sensitive recording and heat-sensitive recording, a method of directly providing a heat-sensitive recording layer on a pressure-sensitive recording layer is the easiest and cheapest method. The recording layer produced is a so-called background fog due to the reaction between the developer in the pressure-sensitive recording layer and the color former in the heat-sensitive recording layer, the whiteness of the non-printed portion is reduced, and the storage stability is poor. Furthermore, there is a problem that the pressure-sensitive and heat-sensitive color density is lowered and the sensitivity is lowered.
Another problem is that for recording sheets that are only partially bonded at the ends, or for recording sheets that are held so that the pins do not slip out by fitting pins into sprocket holes. Is difficult. For this reason, such a recording sheet is often in the form of a continuous form as shown in FIG. 6 of Patent Document 1, but the continuous form is difficult to handle compared to a scroll-like form. There was a problem.

In order to solve these problems of pressure-sensitive and / or heat-sensitive color development performance degradation, an adhesive layer is formed between the recording sheet layers by a dry laminate method or the like, and the layers are bonded and integrated through the adhesive layer. In addition, it can be considered to be a scroll.
At this time, if a pseudo-adhesive layer that is practically used in the field of recording sheets in recent years and that can be peeled off from the two layers to be bonded and cannot be re-applied is provided, In addition, it is considered that a recording sheet can be provided for a wide range of uses that can be separated into two layers via a pseudo-adhesive layer and can be used as, for example, a receipt.

However, in the dry laminating method, a pseudo adhesive is applied to one surface of two target layers and dried, and then the other is laminated and pressure-bonded. Therefore, a high pressure is applied during bonding. Therefore, in the case of a recording sheet having a recording layer capable of pressure-sensitive recording, there is a problem that the recording layer is colored by this pressure, and the resulting recording sheet is stained. For this reason, it has been difficult to put into practical use a recording sheet that includes a recording layer capable of pressure-sensitive recording and heat-sensitive recording, and in which the layers are bonded by a pseudo-adhesive layer.

  The present invention has been made in view of the above circumstances, and a layer including a recording layer capable of pressure-sensitive recording and heat-sensitive recording and, for example, another layer further including a heat-sensitive recording layer are bonded via a pseudo-adhesive layer. It is an object of the present invention to provide a recording sheet that is free from background stains, has excellent storage stability, has high pressure sensitivity and thermal color density, has excellent sensitivity, and can be formed into a scroll shape. .

As a result of intensive studies, the present inventors have provided an intermediate layer containing a specific maleic acid-based copolymer between the pressure-sensitive recording layer and the heat-sensitive recording layer, and a layer having the heat-sensitive recording layer and other layers. It has been found that the above-mentioned problems can be solved by forming a pseudo-adhesion layer for bonding with each other by a wet laminating method, and the present invention has been completed.
The recording sheet of the present invention comprises a first base material layer, a pressure sensitive recording layer capable of pressure sensitive recording, an intermediate layer, a first layer comprising a heat sensitive recording layer capable of thermal recording, and a second base material layer. At least a second layer, and the second layer is a recording sheet laminated on the recording layer side of the first layer via a pseudo-adhesion layer, wherein the pseudo-adhesion layer is formed by a wet lamination method It is characterized by that.
The intermediate layer is preferably a recording sheet containing an alkali salt of an isobutylene / maleic anhydride copolymer.
Further, the pressure-sensitive recording layer of the recording sheet is a self-coloring pressure-sensitive recording layer containing a color former and a developer, and the second layer has a heat-sensitive recording layer. It may be.

  According to the present invention, a layer having a layer capable of pressure-sensitive recording and heat-sensitive recording and another layer having a heat-sensitive recording layer, for example, are bonded via a pseudo-adhesive layer formed by a wet lamination method. In addition, it is possible to provide a recording sheet that is free from background stains, has good storage stability, is excellent in pressure-sensitive and heat-sensitive color development performance, and sensitivity characteristics, and can be formed into a scroll.

The recording sheet of the present invention has a first layer including a first base layer and a recording layer capable of pressure-sensitive recording and thermal recording, and a second layer including at least a second base layer, An intermediate layer is provided between the first pressure-sensitive recording layer and the thermosensitive recording layer, and the second layer is a recording sheet laminated on the first recording layer side via a pseudo-adhesive layer, The pseudo adhesive layer is formed by a wet lamination method.
Hereinafter, the recording sheet of the present invention will be described in detail with reference to exemplary embodiments.
In the present invention, “a recording layer capable of pressure-sensitive recording” refers to a layer that develops color at least under pressure, and in particular, a self-coloring pressure-sensitive recording layer containing a color former and a developer. It is a preferable aspect to provide (first embodiment example).

[First Embodiment]
FIG. 1 shows a pressure-sensitive / heat-sensitive recording sheet 10A of the first embodiment. A self-coloring pressure-sensitive recording layer (pressure-sensitive recording is provided on one side of a first base layer 12). Possible recording layer) 13, intermediate layer 14, and heat-sensitive recording layer 15 are sequentially formed, and first layer 11 and second base material layer 16 are provided with heat-sensitive recording layer 17 on one side and second layer 18. , And laminated through a pseudo adhesive layer 19 formed by a wet lamination method. In this example, the thermosensitive recording layer 15 of the first layer 11 and the second base material layer 16 of the second layer 18 are disposed so as to be adjacent to each other with the pseudo adhesive layer 19 interposed therebetween.
The recording sheet 10 </ b> A of this example records characters, images, and the like by being pressed or heated from the outer surface side of the heat-sensitive recording layer 17 of the second layer 18.

(First base material layer 12 and second base material layer 16)
Here, as the first base material layer 12 and the second base material layer 16, a paper base material mainly containing pulp, a film base material mainly containing various resins, and the like can be used. Although a multi-layered structure composed of a plurality of layers may be used, since the pseudo adhesive layer 19 is formed by a wet laminating method, at least one of the base material layers 12 and 16 has air permeability. Is preferred. That is, as will be described later in detail, when forming the pseudo-adhesive layer 19,
A coating liquid for forming a pseudo-adhesion layer is applied to one side of the first layer 11 or the second layer 18, and the other is bonded together, and then dried. Therefore, the first base layer 12 and / or the second base layer 1
When 6 has air permeability, the solvent in the coating liquid tends to evaporate to the outside.
Although there is no restriction | limiting in particular in the thickness of the 1st base material layer 12, From points, such as adhesive process suitability and handleability,
40-100 micrometers is preferable.

The thickness of the second base material layer 16 is not particularly limited, but the amount of heat transferred to the thermosensitive recording layer 15 of the first layer 11 increases as the thickness of the second base material layer 16 decreases. The recording density of information recorded on the heat-sensitive recording layer 15 is increased and clear. On the other hand, the workability of the second base material layer 16 improves as the thickness increases. From these viewpoints, the second base material layer 16 has a basis weight of 3 to 60 g.
Preferably / a ^{m 2,} and more preferably is 5 to 40 g / ^{m 2.}
Further, as the density of the second base material layer 16 is higher, the amount of heat transferred to the thermosensitive recording layer 15 of the first layer 11 is increased, so that the recording density of information recorded in the thermosensitive recording layer 15 is increased, It becomes clear. When the second base material layer 16 is a paper base material, the higher the density, the higher the transparency.
Therefore, as the 2nd base material layer 16, a density of 0.80 g / cm < ³ > or more is preferable, and the thing in the range of 0.85-1.6 g / cm < ³ > is more preferable. In particular, in the case of a paper substrate, one having a density of 0.85 to 1.3 g / cm ³ is preferable, and in the case of a film substrate,
A density of 0.9 to 1.6 g / cm ³ is preferable.

(Pressure sensitive recording layer 13)
The pressure-sensitive recording layer 13 in this example is a so-called self-coloring material containing a microcapsule containing a color former and a developer, and the microcapsule is destroyed by pressurization, and the color former and the developer are developed. Color is developed by contact and reaction with the agent.
Such a pressure-sensitive recording layer 13 includes a microcapsule containing a color former, includes a layer not containing a developer (hereinafter sometimes referred to as a color former layer), a developer, and a color developer. Contains both microcapsules containing color formers and developer, even in multi-layer structures in which the layers not containing microcapsules (hereinafter sometimes referred to as developer layers) are formed separately. It may be of a single layer structure composed of a layer (hereinafter also referred to as a color former / developer layer).

As the color former, an electron-donating organic color developer is usually used, and as the developer, an electron-accepting organic developer is usually used, but an inorganic developer is used as the developer. Also good.
As the electron-donating organic color former, triarylmethane compounds, diarylmethane compounds, xanthene compounds, thiazine compounds, spiropyran compounds, lactam dyes, fluorane dyes, etc. can be used. Those used for heat-sensitive recording materials can be suitably used. These may be used alone or in combination of two or more.

Specifically, for example, 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide (that is, crystal violet lactone), 3,3-bis (p-dimethylaminophenyl) phthalide, 3- (P-dimethylaminophenyl) -3- (1,2-
Triarylmethane compounds such as dimethylindole-3-yl) phthalide, 4,4-
Diphenylmethane compounds such as bis-dimethylaminobenzhydrylbenzyl ether, N-2,4,5-trichlorophenylleucooramine, 7-diethylamino-3-chlorofluorane, 7-diethylamino-3-chloro-2-methyl Fluorane, fluorane compounds such as 2-phenylamino-3-methyl-6- (N-ethyl-Np-tolylamino) fluorane, thiazine compounds such as benzoylleucomethylene blue and p-nitrobenzoylleucomethylene blue, 3- Spiro compounds such as methyl-spiro-dinaphthopyran, 3-ethyl-spiro-dinaphthopyran, 3-propyl-spiro-dinaphthopyran, 3-propyl-spiro-dibenzopiperane, etc., Japanese Patent Publication Nos. 58-5940 and 49-1
7489, 63-51113, 4-5064, 4-5065, 4-
No. 5066, No. 4-5068, JP-A-62-246352, No. 62-243653, No. 62-257970, No. 62-288078, No. 63-102975, No. 63
-37158, 63-154389, 63-185684, 63-2303
87, JP-A-4-173288, JP-A-5-3240, and the like.

A microcapsule containing a color former is usually in a form of encapsulating droplets in which the color former is dissolved in oil (hereinafter sometimes referred to as capsule oil).
Capsule oils include aromatic synthetic oils such as diarylalkanes, alkylnaphthalenes, alkylated biphenyls, hydrogenated terphenyls, aliphatic synthetic oils such as kerosene, naphtha, paraffin oil, chlorinated paraffin, cottonseed oil, soybean oil, Vegetable oils such as linseed oil can be used, and those generally used for carbonless pressure-sensitive recording materials can be suitably used. Among these, aromatic synthetic oils are particularly preferable from the viewpoints of dye solubility and stability. These may be used alone or in combination of two or more.

In the field of pressure-sensitive recording, gelatin capsules based on the coacervation method have been the mainstream in the past. However, raw materials are cheaply and stably supplied, and high-concentration microcapsule emulsions can be obtained. Synthetic resin-based microcapsules based on the interfacial polymerization method are currently the mainstream because of the simple process. Specifically, a method of producing polyurethane resin, polyurea resin, polyamide resin or the like at the interface of oil and water (Japanese Patent Publication No. 4)
2-446, JP-B 42-771, JP-B 47-1763, JP-B 54-6506
And a method of using an aminoaldehyde resin such as urea-formaldehyde resin, melamine-formaldehyde resin, melamine-urea-formaldehyde resin as a capsule wall membrane by an in-situ polymerization method (JP-A-58-55036). Sho 51-9079,
(JP-A-54-49984, JP-A-56-51238, JP-A-56-102934)
Etc. Also in this example, these synthetic resin microcapsules are preferably used.

The emulsifier used for in situ polymerization encapsulation is preferably a polymer electrolyte.
Specifically, styrene-maleic anhydride copolymer, styrene-benzyl methacrylate-
Maleic anhydride copolymer, α-alkylstyrene-maleic anhydride copolymer, core monoalkyl-substituted styrene-maleic anhydride copolymer, core dialkyl-substituted styrene-maleic anhydride copolymer, styrene-monoalkyl anhydride monoalkyl An aqueous solution of an ester copolymer, an ethylene-maleic anhydride copolymer, polystyrene sulfonic acid, polyacrylic acid, an acrylic acid-acrylic ester copolymer, or a mixed aqueous solution thereof is used.

As the emulsifier used in the interfacial polymerization method, in addition to those exemplified in the in situ polymerization method, aqueous solutions such as PVA, CMC, HEC, various (wheat, potato, corn, etc.) starches, or a mixed aqueous solution thereof may be used. The emulsifier may be used in combination with a known substance having nonionic, cationic or zwitterionic surface activity to the extent that does not cause a problem in microencapsulation.

The size of the microcapsules containing the color former (50% volume average diameter on a Coulter counter) is preferably in the range of 0.5 to 20 μm, particularly preferably in the range of 1 to 10 μm.

The electron accepting organic developer and the inorganic developer are not particularly limited. For example, the organic developer includes a phenol polymer such as a phenol-aldehyde polymer or a phenol-acetylene polymer, or a polyvalent metal salt thereof. Those generally used in the field of carbonless pressure-sensitive recording materials and heat-sensitive recording materials, such as aromatic carboxylic acid compounds such as salicylic acid derivatives and salicylic acid resins, or polyvalent metal salts thereof, are preferably used. These may be used singly or in combination of two or more. Among these, aromatic carboxylic acid compounds and these polyvalent metal salts have high printing density and are resistant to light such as sunlight. It is preferable because of its excellent fastness.

Examples of salicylic acid derivatives include 3-phenyl salicylic acid, 5-phenyl salicylic acid, 3-
Benzylsalicylic acid, 5-benzylsalicylic acid, 3- (α-methylbenzyl) salicylic acid, 5- (α-methylbenzyl) salicylic acid, 3- (α, α-dimethylbenzyl) salicylic acid, 5- (α, α-dimethylbenzyl) Salicylic acid, 3,5-diphenylsalicylic acid, 3
, 5-di (α-methylbenzyl) salicylic acid, 3,5-dibedylsalicylic acid, 3,5-di (α, α-dimethylbenzyl) salicylic acid, 3,5-di (4-methylbenzyl) salicylic acid, etc. And compounds having at least one group substituent. These are preferably used as polyvalent metal salts.
As the salicylic acid-based resin, the above salicylic acid derivative and a styrene derivative such as styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, α-methyl styrene, β-methyl styrene, and the like in a molar ratio of 1: 0.5. 10 to 10 can be exemplified by a salicylic acid-based resin obtained by a Friedel-Crafts reaction under a co-acid catalyst, and a polyvalent metal chloride is preferably used.
Further, salicylic acids disclosed in JP-A-2-563 and polyvalent metal salts composed of the same and polyvalent metal compounds can also be mentioned as preferred developers. As the salicylic acid, a salicylic acid derivative having a total carbon number of 8 or more, particularly 8 to 20 and having an alkyl group is preferably used.
These compounds may be used alone or in combination of two or more.

The polyvalent metal salt is produced, for example, by the following method. Dissolve the salicylic acid derivative in a solvent such as ethers, ketones, and acetates, add the polyvalent metal and inorganic ammonium salt, heat at 40-100 ° C. for 1-6 hours, and filter and distill the product. The unreacted inorganic compound and the solvent are removed.
Specific examples of the polyvalent metal include magnesium, calcium, zinc, aluminum, iron, cobalt, nickel and the like. These may be used alone or in combination of two or more. Zinc is preferred.
Examples of the inorganic developer include acid clay, attapulgite clay, and semi-synthetic solid acid.

When the pressure-sensitive recording layer 13 has a multilayer structure having a color former layer and a developer layer, the color developer layer contains a binder in addition to the microcapsules containing the color former, and the developer layer contains fine particles. In addition to the shaped developer, it contains a binder. Further, the color former layer and the developer layer may contain a pigment as necessary.

Examples of the binder include polyvinyl alcohol and derivatives thereof, starch and derivatives thereof, cellulose derivatives such as hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, methylcellulose, and ethylcellulose, polyacrylic acid soda, polyvinylpyrrolidone, and acrylamide-acrylic acid ester copolymer. Water-soluble polymer materials such as acrylamide-acrylic acid ester-methacrylic acid ester copolymer, styrene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, casein, gelatin and derivatives thereof, and Polyvinyl acetate, polyurethane, polyacrylic acid, polyacrylic ester, vinyl chloride-vinyl acetate copolymer, polybutyl methacrylate, ethylene-vinyl acetate Emulsions and styrene polymers such as - butadiene copolymer, styrene - butadiene - such as latex of water-insoluble polymers such as acrylic copolymers and the like.

Examples of the pigment include inorganic pigments such as light calcium carbonate, heavy calcium carbonate, zinc oxide, magnesium oxide, titanium dioxide, kaolin, clay, calcined kaolin, delaminated kaolin, structured kaolin, magnesium sulfate, and calcium sulfate. Organic pigments (plastic pigment) such as polystyrene resin fine particles, urea formalin resin fine particles, and fine hollow particles are used. These binders and pigments may be used alone or in combination of two or more.
Further, the color former layer and the developer layer may be provided with a water resistance agent, a curing agent, a crosslinking agent, an antifoaming agent, as necessary.
Various additives such as a colorant, a wetting agent, a flow modifier, a preservative, and a surfactant may be included as appropriate.

When the pressure-sensitive recording layer 13 has a single-layer structure composed of a color former / developer layer, the microcapsule containing the color developer, a fine color developer, a binder, and a pigment are included in this layer. And are included. As the binder, pigment, and additive, those exemplified above can be used as appropriate.

(Thermosensitive recording layers 15, 17)
The heat-sensitive recording layers 15 and 17 are colored by heating and contain a reactive dye and a developer-free layer (hereinafter sometimes referred to as a reactive dye layer) and a developer. Even a multilayer structure in which a layer not containing a reactive dye (hereinafter sometimes referred to as a developer layer) is formed separately, a layer containing both a reactive dye and a developer (hereinafter referred to as a developer layer) It may also be a dye / developer layer).

Various types of reactive dyes and developers can be used. Specific combinations of reactive dyes and developers include leuco compounds (leuco dyes) and electron accepting substances, imino compounds and isocyanates. Examples thereof include a narate compound, a long-chain fatty acid iron salt and a polyhydric phenol. Among these, a combination of a leuco compound and an electron-accepting substance is preferable because it has good thermal responsiveness, a high color density, and is relatively stable. A combination of an imino compound and an isocyanate compound is preferable because its color development is hardly affected by the surfactant and is excellent in storage stability.

Examples of the leuco compound include triphenylmethane, fluorane, phenothiazine, auramine, spiropyran, and indinophthalide compounds.
Specifically, 3,3-bis (p-dimethylaminophenyl) -phthalide, 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide, 3,3-bis (p-dimethylamino) Phenyl) -6-diethylaminophthalide, 3,3-bis (p-dimethylaminophenyl) -6-chlorophthalide, 3,3-bis (p-dibutylaminophenyl) phthalide, 3-cyclohexylamino-6-chlorofluorane 3-dimethylamino-5
7-dimethylfluorane, 3-N-methyl-N-isobutyl-6-methyl-7-anilinofluorane, 3-N-ethyl-N-isoamyl-6-methyl-7-anilinofluorane,
3-diethylamino-7-chlorofluorane, 3-diethylamino-7-methylfluorane, 3-diethylamino-7,8-benzfluorane, 3-diethylamino-6-methyl-7-chlorofluorane, 3- (N -Ethyl-Np-tolyl) -6-methyl-7-anilinofluorane, 3- (Np-tolyl-N-ethylamino) -6-methyl-7-anilinofluorane, 3-pyrrolidino -6-methyl-7-anilinofluorane, 2- {N-3 '
-Trifluoromethylphenyl) amino} -6-diethylaminofluorane, 2- {3,
6-bis (diethylamino) -9- (o-chloroanilino) xanthylbenzoate lactam}, 3-diethylamino-6-methyl-7- (m-trichloromethylanilino) fluorane, 3-diethylamino-7- (o-chloroanilino) ) Fluorane, 3-dibutylamino-7- (o-chloroanilino) fluorane, 3-N-methyl-N-amylamino-6-methyl-7-anilinofluorane, 3-N-methyl-N-cyclohexylamino-6 -Methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7- (2 ', 4'-dimethylanilino) fluorane, 3- (N, N-diethylamino) -5-methyl-7- (N, N-dibenzylamino) fluorane, benzoylleuco Methylene blue, 6'-chloro-8'-methoxy-benzoindolino-pyrospirane, 6'-bromo-3'-methoxy-benzoindolino-
Pyrrirospirane, 3- (2′-hydroxy-4′-dimethylaminophenyl) -3- (2
'-Methoxy-5'-chlorophenyl) phthalide, 3- (2'-hydroxy-4'-dimethylaminophenyl) -3- (2'-methoxy-5'-nitrophenyl) phthalide, 3-
(2′-Hydroxy-4′-diethylaminophenyl) -3- (2′-methoxy-5′-
Methylphenyl) phthalide, 3- (2′-methoxy-4′-dimethylaminophenyl)-
3- (2′-hydroxy-4′-chloro-5′-methylphenyl) phthalide, 3-morpholino-7- (N-propyl-trifluoromethylanilino) fluorane, 3-pyrrolidino-7-trifluoromethylani Linofluorane, 3-diethylamino-5-chloro-7-
(N-benzyl-trifluoromethylanilino) fluorane, 3-pyrrolidino-7- (di-p-chlorophenyl) methylaminofluorane, 3-diethylamino-5-chloro-7
-(Α-phenylethylamino) fluorane, 3- (N-ethyl-p-toluidino) -7
-(Α-phenylethylamino) fluorane, 3-diethylamino-7- (o-methoxycarbonylphenylamino) fluorane, 3-diethylamino-5-methyl-7- (α-
Phenylethylamino) fluorane, 3-diethylamino-7-piperidinofluorane,
2-chloro-3- (N-methyltoluidino) -7- (pn-butylanilino) fluorane, 3- (N-methyl-N-isopropylamino) -6-methyl-7-anilinofluorane, 3-dibutyl Amino-6-methyl-7-anilinofluorane, 3,6-bis (dimethylamino) fluorene spiro (9,3 ')-6'-dimethylaminophthalide, 3- (N-
Benzyl-N-cyclohexylamino) -5,6-benzo-7-α-naphthylamino-4
'-Bromofluorane, 3-diethylamino-6-chloro-7-anilinofluorane, 3
-N-ethyl-N- (2-ethoxypropyl) amino-6-methyl-7-anilinofluorane, 3-N-ethyl-N-tetrahydrofurfurylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-mesitidino-4 ′, 5′-benzofluorane and the like.
These leuco compounds may be used alone or in combination of two or more.

The electron-accepting substance that contacts the leuco compound and develops color is not particularly limited,
Examples thereof include phenolic compounds, thiophenolic compounds, thiourea derivatives, organic acids and metal salts thereof.
Specifically, 4-tert-butylphenol, 4-acetylphenol, 4-tert
-Octylphenol, 4,4'-sec-butylidene diphenol, 4-phenylphenol, 4,4'-dihydroxydiphenylmethane, 4,4'-isopropylidenediphenol, 4,4'-cyclohexylidene diphenol, 1,1 -Bis (4-hydroxyphenyl) -1-phenylethane, 4,4'-dihydroxydiphenyl sulfide, 4,
4′-thiobis (3-methyl-6-tert-butylphenol), 4,4′-dihydroxydiphenylsulfone, 2,4′-dihydroxydiphenylsulfone, 4-hydroxy-4′-isopropoxydiphenylsulfone, and bis (3 Phenolic compounds such as -allyl-4-hydroxyphenyl) sulfone, bis (p-hydroxyphenyl) butyl acetate, methyl bis (p-hydroxyphenyl) acetate, 4-hydroxybenzophenone,
Dimethyl 4-hydroxyphthalate, methyl 4-hydroxybenzoate, propyl 4-hydroxybenzoate, 4-hydroxybenzoate-sec-butyl, phenyl 4-hydroxybenzoate, benzyl 4-hydroxybenzoate, 4-hydroxybenzoic acid Tolyl, phenolic compounds such as 4-hydroxybenzoic acid chlorophenyl, 4,4′-dihydroxydiphenyl ether, or benzoic acid, p-tert-butylbenzoic acid, trichlorobenzoic acid,
Terephthalic acid, salicylic acid, 3-tert-butylsalicylic acid, 3-isopropylsalicylic acid, 3-benzylsalicylic acid, 3- (α-methylbenzyl) salicylic acid, 3,5-di-
Aromatic carboxylic acids such as tert-butylsalicylic acid, and these phenolic compounds, organic acidic substances such as salts of aromatic carboxylic acids with polyvalent metals such as zinc, magnesium, aluminum and calcium, Np-toluenesulfonyl -N'-3- (p-toluenesulfonyloxy) phenylurea, N- (p-toluenesulfonyl) -N '-(p-
And urea compounds such as butoxycarboyl) urea and Np-tolylsulfonyl-N′-phenylurea. These electron accepting substances may be used alone or in combination of two or more.

The imino compound is a compound having at least one imino group (═NH), and examples thereof include a normal temperature solid colorless or light-colored compound represented by the following general formula.

［式中、Ｘは、隣接するＣ＝Ｎと共役系を形成しうる芳香族性化合物残基を表す。］

[Wherein X represents an aromatic compound residue capable of forming a conjugated system with adjacent C═N. ]

Specifically, as the imino compound, 3-iminoisoindoline-1-one, 3-imino-4,5,6,7-tetrachloroisoindoline-1-one, 3-imino-4,5,6,
7-tetrabromoisoindoline-1-one, 3-imino-4,5,6,7-tetrafluoroisoindoline-1-one, 3-imino-5,6-dichloroisoindoline-1-one, 3- Imino-4,5,7-trichloro-6-methoxy-isoindoline-1-one,
3-imino-4,5,7-trichloro-6-methylmercapto-isoindoline-1-one, 3-imino-6-nitroisoindoline-1-one, 3-imino-isoindoline-
1-spiro-dioxolane, 1,1-dimethoxy-3-imino-isoindoline, 1,1
-Diethoxy-3-imino-4,5,6,7-tetrachloroisoindoline, 1-ethoxy-3-imino-isoindoline, 1,3-diiminoisoindoline, 1,3-diimino-4,5 6,7-tetrachloroisoindoline, 1,3-diimino-6-methoxyisoindoline, 1,3-diimino-6-cyanoisoindoline, 1,3-diimino-4,7
-Dithia-5,5,6,6-tetrahydroisoindoline, 7-amino-2,3-dimethyl-5-oxopyrrolo [3,4b] pyrazine, 7-amino-2,3-diphenyl-5-oxopyrrolo [3 , 4b] pyrazine, 1-iminonaphthalimide, 1-iminodiphenimide, 1-phenylimino-3-iminoisoindoline, 1- (3′-chlorophenylimino) -3-iminoisoindoline, 1- (2 ′, 5'-dichlorophenylimino)-
3-iminoisoindoline, 1- (2 ′, 4 ′, 5′-trichlorophenylimino) -3
-Iminoisoindoline, 1- (2'-cyano-4'-nitrophenylimino) -3-iminoisoindoline, 1- (2'-chloro-5'-cyanophenylimino) -3-iminoisoindoline, 1 -(2 ', 6'-dichloro-4'-nitrophenylimino) -3-iminoisoindoline, 1- (2', 5'-dimethoxyphenylimino) -3-iminoisoindoline, 1- (2 ', 5′-diethoxyphenylimino) -3-iminoisoindoline, 1- (2′-methyl-4′-nitrophenylimino) -3-iminoisoindoline,
1- (5′-chloro-2′-phenoxyphenylimino) -3-iminoisoindoline, 1- (4′-N, N-dimethylaminophenylimino) -3-iminoisoindoline,
1- (3′-N, N-dimethylamino-4′-methoxyphenylimino) -3-iminoisoindoline, 1- (2′-methoxy-5′-N-phenylcarbamoylphenylimino) -3-iminoiso Indoline, 1- (2′-chloro-5′-trifluoromethylphenylimino) -3-iminoisoindoline, 1- (5 ′, 6′-dichlorobenzothiazolyl-2′-imino) -3-imino Isoindoline, 1- (6′-methylbenzothiazolyl-
2′-imino) -3-iminoisoindoline, 1- (4′-phenylaminophenylimino) -3-iminoisoindoline, 1- (p-phenylazophenylimino) -3-iminoisoindoline, 1- ( Naphthyl-1′-imino) -3-iminoisoindoline, 1-
(Anthraquinone-1′-imino) -3-iminoisoindoline, 1- (5′-chloroanthraquinone-1′-imino) -3-iminoisoindoline, 1- (N-ethylcarbazolyl-3 ′) -Imino) -3-iminoisoindoline, 1- (naphthoquinone-1'-imino) -3-iminoisoindoline, 1- (pyridyl-4'-imino) -3-iminoisoindoline, 1- (benzimidazolone) -6'-imino) -3-iminoisoindoline, 1-
(1′-methylbenzimidazolone-6′-imino) -3-iminoisoindoline, 1-
(7′-chlorobenzimidazolone-5′-imino) -3-iminoisoindoline, 1-
(Benzimidazolyl-2′-imino) -3-iminoisoindoline, 1- (benzimidazolyl-2′-imino) -3-imino-4,5,6,7-tetrachloroisoindoline, 1- (2 ′ , 4′-dinitrophenylhydrazone) -3-iminoisoindoline, 1-
(Indazolyl-3'-imino) -3-iminoisoindoline, 1- (indazolyl-3
'-Imino) -3-imino-4,5,6,7-tetrabromoisoindoline, 1- (indazolyl-3'-imino) -3-imino-4,5,6,7-tetrafluoroisoindoline, 1- (Benzimidazolyl-2′-imino) -3-imino-4,7-dithiatetrahydroisoindoline, 1- (4 ′, 5′-dicyanoimidazolyl-2′-imino) -3-
Imino-5,6-dimethyl-4,7-pyradiisoindoline, 1- (cyanobenzoylmethylene) -3-iminoisoindoline, 1- (cyanocarbonamidomethylene) -3-iminoisoindoline, 1- (cyano Carbomethoxymethylene) -3-iminoisoindoline, 1- (cyanocarboethoxymethylene) -3-iminoisoindoline, 1- (cyano-N-phenylcarbamoylmethylene) -3-iminoisoindoline, 1- [cyano-N
-(3'-methylphenyl) -carbamoylmethylene] -3-iminoisoindoline, 1
-[Cyano-N- (4'-chlorophenyl) -carbamoylmethylene] -3-iminoisoindoline, 1- [cyano-N- (4'-methoxyphenyl) -carbamoylmethylene]
-3-Iminoisoindoline, 1- [cyano-N- (3'-chloro-4'-methylphenyl) -carbamoylmethylene] -3-iminoisoindoline, 1- (cyano-p-nitrophenylmethylene) -3 -Iminoisoindoline, 1- (dicyanomethylene) -3-iminoisoindoline, 1- [cyano-1 ', 2', 4'-triazolyl- (3 ')-carbamoylmethylene] -3-iminoisoindoline, 1 -[Cyanothiazoyl- (2 ')-carbamoylmethylene] -3-iminoisoindoline, 1- [cyanobenzimidazolyl-
(2 ′)-carbamoylmethylene] -3-iminoisoindoline, 1- [cyanobenzothiazolyl- (2 ′)-carbamoylmethylene] -3-iminoisoindoline, 1- [cyanobenzimidazolyl- (2 ′) -Methylene] -3-iminoisoindoline, 1- [cyanobenzimidazolyl- (2 ')-methylene] -3-imino-4,5,6,7-tetrachloroisoindoline, 1-[(cyanobenzimidazolyl- 2 ')-methylene] -3-imino-5-methoxyisoindoline, 1-[(cyanobenzimidazolyl-2')-methylene] -3-imino-6-chloroisoindoline, 1-[(1'-phenyl) -3'-methyl-5-oxo) -pyrazolidene-4 ']-3-iminoisoindoline, 1-[(cyanobenzimidazolyl-2')-methylene]- 3-imino-4,7-dithiatetrahydroisoindoline, 1-[(cyanobenzimidazolyl-2 ′)-methylene] -3-imino-
5,6-dimethyl-4,7-pyradiisoindoline, 1-[(1'-methyl-3'-n-
Butyl) -barbituric acid-5 ′]-3-iminoisoindoline, 3-imino-1-sulfobenzoimide, 3-imino-1-sulfo-6-chlorobenzoimide, 3-imino-1
-Sulfo-5,6-dichlorobenzoimide, 3-imino-1-sulfo-4,5,6,7
-Tetrachlorobenzoic acid imide, 3-imino-1-sulfo-4,5,6,7-tetrabromobenzoic acid imide, 3-imino-1-sulfo-4,5,6,7-tetrafluorobenzoic acid imide, 3-imino-1-sulfo-6-nitrobenzoimide, 3-imino-1-sulfo-6-methoxybenzoimide, 3-imino-1-sulfo-4,5,7-trichloro-6
-Methyl mercaptobenzoic acid imide, 3-imino-1-sulfonaphthoic acid imide, 3-imino-1-sulfo-5-bromonaphthoic acid imide, 3-imino-2-methyl-4,5,6
7-tetrachloroisoindoline-1-one and the like.

Examples of the isocyanate compound that contacts with an imino compound to develop a color include colorless or light-colored aromatic isocyanate compounds or heterocyclic isocyanate compounds that are solid at room temperature, and specifically, 2,6-dichlorophenyl isocyanate. P-chlorophenyl isocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 1,3-dimethylbenzene-4,6-diisocyanate, 1,4-dimethylbenzene-2,5 -Diisocyanate, 1-methoxybenzene-2,4-diisocyanate, 1-
Methoxybenzene-2,5-diisocyanate, 1-ethoxybenzene-2,4-diisocyanate, 2,5-dimethoxybenzene-1,4-diisocyanate, 2,5-diethoxybenzene-1,4 -Diisocyanate, 2,5-dibutoxybenzene-1,4-diisocyanate, azobenzene-4,4'-diisocyanate, diphenyl ether-4,
4'-diisocyanate, naphthalene-1,4-diisocyanate, naphthalene-1,5
-Diisocyanate, naphthalene-2,6-diisocyanate, naphthalene-2,7-diisocyanate, 3,3'-dimethyl-biphenyl-4,4'-diisocyanate, 3,
3'-dimethoxybiphenyl-4,4'-diisocyanate, diphenylmethane-4,4
'-Diisocyanate, diphenyldimethylmethane-4,4'-diisocyanate, benzophenone-3,3'-diisocyanate, fluorene-2,7-diisocyanate, anthraquinone-2,6-diisocyanate 9-ethylcarbazole-3,6-diisocyanate, bilene-3,8-diisocyanate, naphthalene-1,3,7-triisocyanate, biphenyl-2,4,4′-triisocyanate, 4 , 4 ′, 4 ″ -triisocyanato-2,5-dimethoxytriphenylamine, 4,4 ′, 4 ″ -triisocyanatotriphenylamine, p-dimethylaminophenyl isocyanate, tris (4-phenylisocyanate) ) Thiophosphate and the like. These isocyanate compounds may be used in the form of so-called block isocyanate, which is an addition compound with phenols, lanthanums, oximes, etc., if necessary. Diisocyanate dimer, for example, 1
-It may be used in the form of dimer of methylbenzene-2,4-diisocyanate and isocyanurate which is trimer, and can also be used as polyisocyanate adducted with various polyols It is.

The content of the reactive dye in the heat-sensitive recording layers 15 and 17 is preferably 10 to 50% by mass and more preferably 10 to 20% by mass in the heat-sensitive recording layers 15 and 17 in consideration of color developability. The developer content in the heat-sensitive recording layers 15 and 17 is 100 to 7 with respect to 100 parts by mass of the reactive dye.
00 parts by mass is preferable, and 150 to 400 parts by mass is more preferable.

The heat-sensitive recording layers 15 and 17 further contain a binder in addition to the reactive dye and the developer.
The binder can be appropriately selected from those exemplified in the pressure-sensitive recording layer 13.
The binder content in the heat-sensitive recording layers 15 and 17 is 5 to 40 in the heat-sensitive recording layers 14 and 17.
% By mass is preferable, and 10 to 30% by mass is more preferable.

The heat-sensitive recording layers 15 and 17 preferably further contain a sensitizer in order to adjust the color development sensitivity. As the sensitizer, a compound conventionally known as a sensitizer for a heat-sensitive recording material can be used. For example, an organic substance having a relatively low melting point and a good compatibility with a reactive dye and a developer (hereinafter referred to as a sensitizer)
A heat fusible substance). The heat-fusible substance is compatible with a reactive dye and a developer, thereby increasing the contact probability between these two components and exerting a sensitizing action.
Examples of the heat-fusible substance include parabenzyl biphenyl, dibenzyl terephthalate,
Phenyl 1-hydroxy-2-naphthoate, dibenzyl oxalate, di-o-chlorobenzyl adipate, 1,2-di (3-methylphenoxy) ethane, di-p-methylbenzyl oxalate, di-p oxalate -Chlorobenzyl, 1,2-bis (3,4-dimethylphenyl)
Examples thereof include ethane, 1,3-bis (2-naphthoxy) propane, and the like.
The content of the heat fusible substance in the thermosensitive recording layers 15 and 17 is based on 100 parts by mass of the reactive dye.
25-500 mass parts is preferable, and 100-300 mass parts is more preferable.

The heat-sensitive recording layers 15 and 17 may further contain an image stabilizer for the main purpose of improving the preservability of heat-recorded characters and images.
Examples of the image stabilizer include 1,1,3-tris (2-methyl-4-hydroxy-5
-Cyclohexylphenyl) butane, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,1-bis (2-methyl-4-hydroxy-5-tert-butyl) Phenyl) butane, 4,4 ′-[1,4-phenylenebis (1-
Methylethylidene)] bisphenol, and 4,4 ′-[1,3-phenylenebis (1
-Methylethylidene)] phenolic compounds such as bisphenol, 4-benzyloxyphenyl-4 '-(2-methyl-2,3-epoxypropyloxy) phenylsulfone, 4- (2-methyl-1,2-epoxy Ethyl) diphenylsulfone, and 4- (2-
Ethyl-1,2-epoxyethyl) diphenylsulfone and the like, and 1,
3,5-tris (2,6-dimethylbenzyl-3-hydroxy-4-tert-butyl)
One or more selected from isocyanuric acid compounds such as isocyanuric acid can be used.
The content of the image stabilizer in the heat-sensitive recording layers 15 and 17 is based on 100 parts by mass of the reactive dye.
5-100 mass parts is preferable and 10-60 mass parts is more preferable.

The heat-sensitive recording layers 15 and 17 may contain a crosslinking agent for three-dimensionally curing the above-described binder in order to improve water resistance.
Examples of the crosslinking agent include aldehyde compounds such as glyoxal, polyamine compounds such as polyethyleneimine, epoxy compounds, polyamide resins, melamine resins, dimethylol urea compounds, aziridine compounds, blocked isocyanate compounds, ammonium persulfate and Examples thereof include diiron, and inorganic compounds such as magnesium chloride, sodium tetraborate, and potassium tetraborate, or boric acid, boric acid triesters, and boron-based polymers.
The blending amount of the crosslinking agent in the thermosensitive recording layers 15 and 17 is preferably in the range of 1 to 10% by mass in the thermosensitive recording layers 15 and 17.

The thermosensitive recording layers 15 and 17 may contain a pigment.
Examples of the pigment include calcium carbonate, magnesium carbonate, kaolin, clay, talc, calcined clay, silica, diatomaceous earth, synthetic aluminum silicate, zinc oxide, titanium oxide, aluminum hydroxide, barium sulfate, and surface-treated calcium carbonate. And inorganic pigments such as silica and silica, and organic pigments such as urea-formalin resin, styrene-methacrylic acid copolymer resin, and polystyrene resin.
The pigment content in the heat-sensitive recording layers 15 and 17 is preferably an amount that does not decrease the color density, and is preferably 50% by mass or less in the heat-sensitive recording layers 15 and 17.
Moreover, 1-100 mass parts is preferable with respect to 100 mass parts of reactive dye, and 5-50 mass parts is more preferable.

Various additives generally used in thermal recording media can be added to the thermal recording layers 15 and 17 as necessary. Examples of the additive include waxes, metal soaps, colored dyes, fluorescent dyes, oil repellents, antifoaming agents, viscosity modifiers and the like.
Examples of waxes include waxes such as paraffin wax, carnauba wax, microcrystalline wax, and polyolefin wax such as polyethylene wax, and higher fatty acid amides such as stearic acid amide and ethylenebisstearic acid amide, higher fatty acid esters, And derivatives thereof.
In particular, when methylolated fatty acid amide is added to the heat-sensitive recording layers 15 and 17, a sensitizing effect can be obtained without deteriorating the background fog resistance.
Examples of the metal soap include higher fatty acid polyvalent metal salts such as zinc stearate, aluminum stearate, calcium stearate, and zinc oleate.

(Intermediate layer 14)
The intermediate layer of the present invention is provided between the pressure-sensitive recording layer 13 and the heat-sensitive recording layer 15, and the developer component and the color former component of each layer are directly contacted in a normal state (for example, room temperature). It is only necessary to have a film forming property for preventing movement.

The intermediate layer preferably contains an alkali salt of an isobutylene / maleic anhydride copolymer. The reason is that by providing an intermediate layer between the pressure-sensitive layer and the heat-sensitive layer, the contact between the developer component of the pressure-sensitive layer and the color former component of the heat-sensitive layer is inhibited. By including an alkali salt of a maleic acid copolymer in the intermediate layer, the effect of suppressing the reaction between the developer component and the color developer component becomes remarkable, and the respective color developer and developer component become the original color reaction. In order to contribute effectively, it is considered that the color development performance as a recording sheet is excellent and the effect of improving the sensitivity characteristic is obtained.

Examples of the alkali salt include a sodium salt and an ammonium salt. Among them, an ammonium salt is preferably used.

In addition to the copolymer of the present invention, for example, oxidized starch, phosphate esterified starch, enzyme-modified starch, acetate esterified starch, soy protein, synthetic protein, methylcellulose, carboxymethylcellulose, hydroxymethylcellulose, polyvinyl alcohol and the like are water-soluble. Adhesives and / or water-dispersible adhesives such as styrene-butadiene latex, acrylic latex, acrylic-butadiene latex, acrylonitrile-butadiene latex, vinyl acetate latex, urethane resin, melamine resin, etc. Can do.
When used in combination, the blending amount of the alkali salt of the isobutylene / maleic anhydride copolymer is 10% or more, preferably 30% or more of the total solid content of the intermediate layer. If the blending amount is less than 10%, the desired effect may not be obtained.

  In the practice of the present invention, in addition to the alkali salt of the above-mentioned isobutylene / maleic anhydride copolymer, an antifoaming agent, a coloring agent, a fluorescent dye, a water-resistant agent, a crosslinking agent, a lubricant, as necessary, Various auxiliary agents such as fluidity modifiers and preservatives can be appropriately blended and used.

(Pseudo adhesive layer 19)
The pseudo adhesive layer 19 in this example adheres the first layer 11 and the second layer 18 so that they can be peeled off and cannot be re-applied, and is formed by a wet laminating method.
The pseudo-adhesive layer 19 preferably contains various pseudo-adhesives that can be used for pseudo-adhesion and can be applied with a wet laminating method as an adhesive component, and further contains an adhesive force regulator.
Examples of such a pseudo-adhesive include rubber-based pressure-sensitive adhesives such as natural rubber and synthetic rubber; acrylic pressure-sensitive adhesives containing acrylic acid and / or acrylic acid ester as a main monomer component; vinyl acetate polymer, ethylene- Vinyl acetate adhesives containing vinyl acetate as the main monomer component, such as vinyl acetate copolymer (EVA); polysaccharide adhesives such as starch and sodium alginate, and water-soluble adhesives such as dextrin adhesives are used it can.
Among these, rubber-based, acrylic-based, vinyl acetate-based, and dextrin-based adhesives
Adhesive properties can be controlled in a wide range, which is preferable and is appropriately selected in consideration of adhesive strength and the like. Furthermore, since this pseudo adhesive layer 19 is formed by a wet laminating method, in particular, vinyl acetate type and / or dextrin type The pressure sensitive adhesive is preferred.
10-100 mass% is preferable in the pseudo adhesive layer 19, and, as for content of the pseudo adhesive in the pseudo adhesive layer 19, 20-80 mass% is more preferable.

Examples of the adhesive strength modifier include waxes such as polyethylene wax exemplified as additives contained in the heat-sensitive recording layers 15 and 17, metal soap, inorganic pigments, organic pigments, and the like. These adhesive force regulators are dispersed in the pseudo adhesive layer 19 and have an effect of reducing the cohesive force of the pseudo adhesive layer 19. By reducing the cohesive force of the pseudo adhesive layer 19, the first layer 11 and the second layer 18 are easily peeled off.
The content of the adhesive strength adjusting agent in the pseudo adhesive layer 19 is appropriately determined in consideration of the adhesive strength between the first layer 11 and the second layer 18, the cohesive force of the pseudo adhesive layer 19, and the like. In particular, it is preferable that the amount of the adhesive strength between the first layer 11 and the second layer 18 be in the range described later. For example, in the pseudo adhesive layer 19, 0 to 90% by mass is preferable, and 20 -80 mass% is more preferable.

The adhesive strength between the first layer 11 and the second layer 18 in the pseudo adhesive layer 19 is JIS K 6
50-1000 mN / 25 mm (in accordance with the T-type peeling test method specified in 854-3
Peeling speed is preferably 300 mm / min), and further 80 to 600 mN / 25 m
m (peeling speed 300 mm / min) is more preferable.
If the adhesion strength according to the T-peeling test method is less than 50 mN / 25 mm, the first layer 11 and the second layer 18 may be easily peeled off or the appearance may deteriorate due to curling or wrinkling. .
If the adhesive strength by the T-peeling test method exceeds 1000 mN / 25 mm, the first layer 11
When the first layer 11 and the second layer 18 are peeled off, the first layer 11 and / or the second layer 18 may be damaged, and a strong curl in the flow direction is likely to become a cylindrical shape.
The adhesive strength according to the T-peeling test method can be appropriately adjusted according to the type of pseudo-adhesive used, the permeability based thereon, the coating amount, the time from application to bonding, the drying temperature, and the like.

Here, the adhesive strength according to the T-type peeling test method defined in JIS K 6854-3 can be measured by the following procedure. That is, after leaving the sample in an environment of 23 ° C. and 50% RH for 24 hours or more, a peeling test is performed at a peeling speed of 300 mm / min. The bond strength is expressed in mN per 25 mm test sample width.

(Method for producing recording sheet 10A)
The manufacturing method of the recording sheet 10A in the example of FIG. 1 is not limited as long as it is a method in which the first layer 11 and the second layer 18 are bonded by the pseudo-adhesive layer 19 by a wet laminating method. A method of forming the heat-sensitive recording layer 17 on the second base material layer 16 after adhering 11 and the second base material layer 16 to each other with the pseudo-adhesive layer 19 by the wet laminating method is preferable. According to this method, a recording sheet 10 </ b> A that is less likely to cause wrinkles or the like on the second base material layer 16 and has an excellent appearance can be obtained. For example, when the second base material layer 16 is a paper base material, water may be absorbed when the pseudo adhesive layer 19 is formed, and elongation, wrinkles, paper breakage, etc. may occur, and it is a film base material. In some cases, particularly when the thickness is small, the waist may become weak and deformation such as wrinkles may occur or it may become difficult to handle. On the other hand, after bonding the first layer 11 and the second base material layer 16 with the pseudo-adhesive layer 19, by forming the thermosensitive recording layer 17 on the second base material layer 16, these You can improve the problem.

As a specific manufacturing method, first, a coating liquid for forming the pressure-sensitive recording layer 13 (hereinafter sometimes referred to as a pressure-sensitive recording layer forming coating liquid) is prepared, and this is used as the first manufacturing method. It is applied to one side of the substrate layer 12 and dried.
Here, when the pressure-sensitive recording layer 13 has a multilayer structure in which a color former layer and a developer layer are separately formed, a coating solution for forming a color former layer is formed as a pressure-sensitive recording layer forming coating solution. A working solution and a coating solution for forming a developer layer are respectively prepared, and one of them is applied to one side of the first base layer 12 and dried, and then the other is applied and dried. . The coating liquid for forming the color former layer is obtained by dispersing microcapsules containing a color former, a binder, and, if necessary, pigments and additives in a dispersion medium such as water. In order to form the agent layer, the coating liquid can be obtained by dispersing a fine particle developer, a binder, and a pigment or an additive used as necessary in a dispersion medium such as water.

In this case, either the color former layer or the developer layer may be formed so as to be in contact with the first base material layer 12, but the recording sheet 10 </ b> A in this example is formed of the heat-sensitive recording layer 17 of the second layer 18. Since it is recorded by being pressurized from the outer surface side, a color developer layer having a microcapsule containing a color developer is formed on the developer layer so as to be in contact with the first base material layer 12. It is preferable that the microcapsules are formed because the microcapsules are easily broken by pressurization.
Further, the coating solution for forming a color former layer is preferably subjected to a 2.0~7.0g / m ² coating on a dry weight, 3.0~6.0g / m ² is more preferable. The coating liquid for forming the developer layer is preferably applied in a dry mass of 3.0 to 10.0 g / m ^2.
7.0 g / m ² is more preferable.

On the other hand, when the pressure-sensitive recording layer 13 has a single layer structure composed of a color former / developer layer, the color former, the developer, the binder, and the pigment or additive used as necessary are water or the like. A pressure-sensitive recording layer forming coating liquid dispersed in the above dispersion medium is prepared, and this is applied to one side of the first base material layer 12 and dried. In this case, it is preferable to apply 5.0 to 15.0 g / m ² in terms of dry mass, and 7.0
˜10.0 g / m ² is more preferable.

For the preparation of each coating solution, for example, a stirring / pulverizing machine such as a ball mill, an attritor, or a sand mill can be used.
An air knife coater, a blade coater, a short dwell coater, a rod blade coater, a roll coater, a bar coater, a size press coater, a bill blade coater, or the like can be used for coating each coating solution. Among these, air knife coaters,
When a curtain coater, a die coater, or the like is used, an excessive pressure is not applied to the object to be coated. Therefore, a color former layer containing microcapsules is already formed on the first base material layer 12. In the case of forming a developer layer, it is preferable to select these coaters in order to suppress the destruction of the microcapsules.

Next, a coating liquid for forming the intermediate layer 14 (hereinafter sometimes referred to as an intermediate layer forming coating liquid) is applied onto the pressure-sensitive recording layer 13 and dried to form the intermediate layer 14. .
The coating amount of the intermediate layer coating liquid, 0.5 to 5 g / ^{m 2} by dry weight, preferably 1.0 to 3.0 g / ^{m 2} coating. For the preparation and application of the intermediate layer forming coating solution, various stirring / pulverizing machines exemplified in the formation of the pressure-sensitive recording layer 13 and various coaters can be used.

In this way, the pressure-sensitive recording layer 13 is formed on the first base material layer 12, the intermediate layer 14 is formed on the pressure-sensitive recording layer 13, and then the heat-sensitive recording layer 15 is further formed on the intermediate layer 14. A heat-sensitive recording layer 15 is formed by applying and drying a coating liquid for forming (hereinafter also referred to as a heat-sensitive recording layer-forming coating liquid).
Here, the heat-sensitive recording layer 15 may have a multilayer structure in which the reactive dye layer and the developer layer are separately formed as described above, but a dye containing both the reactive dye and the developer. -A single-layer structure composed of a developer layer is preferred because of excellent reactivity and thermal response.
In this case, a reactive dye, a developer, a binder, and, if necessary, a pigment or an additive are dispersed in a dispersion medium such as water to prepare a coating solution for forming a thermal recording layer. Is applied onto the already formed intermediate layer and dried. In this case, the reactive dye and the developer are dispersed in different dispersion media to prepare two types of dispersions, and these two types of dispersions are mixed when the thermal recording layer 15 is formed. It is preferable.

The coating amount of the heat-sensitive recording layer forming coating solution is 1 to 10 in terms of dry mass in consideration of color developability.
preferably ^{g / m 2, 2~5g / m} 2 is more preferable.
In addition, various stirrers / pulverizers and various coaters exemplified in the formation of the pressure sensitive recording layer 13 can be used for the preparation and application of the heat sensitive recording layer forming coating solution.

Thus, the heat-sensitive recording layer 15 is formed, and the first layer 11 in which the first base material layer 12, the pressure-sensitive recording layer 13, the intermediate layer 14, and the heat-sensitive recording layer 15 are sequentially formed is obtained.
The outer surface of the thermosensitive recording layer 15 may be smoothed using a known smoothing method such as a super calendar or a soft calendar. Thereby, the coloring sensitivity can be increased. In the smoothing process, the outer surface of the thermosensitive recording layer 15 may be applied to either a calendar metal roll or an elastic roll.

Next, a coating liquid for forming the pseudo adhesive layer 19 (hereinafter, also referred to as a pseudo adhesive layer forming coating liquid) is prepared. And this is apply | coated to the surface of the heat-sensitive recording layer 15 of the 1st layer 11, or the 2nd base material layer 16, The 1st layer 11 and the 2nd base material layer 16 are dried without drying this coating liquid. After bonding, the first layer 11 and the second base material layer 1 are dried by a wet laminating method.
6 is produced by bonding the recording sheet 6 with the pseudo adhesive layer 19.
As the coating solution for forming the pseudo-adhesive layer, a water-based emulsion of a pseudo-adhesive such as vinyl acetate, or a solution obtained by dissolving a water-soluble pseudo-adhesive such as a dextrin in water is preferable. Can be used, and if necessary, an adhesive strength modifier is blended. The application method of this coating liquid can be performed in the same manner as the pressure-sensitive recording layer 13 in the first layer 11.
The coating amount of the pseudo-adhesive layer-forming coating solution is 0.5 to 10 because of excellent recording characteristics.
preferably ^{g / m 2, 1~5g / m} 2 is more preferable.

According to such a wet laminating method, the first application is performed before the applied coating liquid is dried.
Since the layer 11 and the second layer 18 are bonded together, almost no pressure is required at the time of bonding, and a sufficient pseudo-bonding can be achieved even at a linear pressure of 980 N / m (1 kg / cm) or less. Therefore, even when the first layer 11 has the pressure-sensitive recording layer 13 that develops color by pressurization as in this example, the pressure-sensitive recording layer 13 does not develop color by pressurization during bonding, No background stains occur. Furthermore, according to the wet laminating method, the moisture in the coating liquid acts as a buffer material during the bonding, and thus there is an advantage that the pressure transmitted to the pressure-sensitive recording layer 13 during the bonding is further relaxed. Here, if a dry laminating method is employed in which the adhesive is applied to the first layer and then dried and then the second base material layer is pressure-bonded, a linear pressure of 19600 N / m (2
It is necessary to press-bond with a pressure of about 0 kg / cm), and in this method, the soil is caused on the pressure-sensitive recording layer due to pressurization at the time of bonding. Moreover, even if it is going to employ | adopt the extrusion lamination method which extrudes high temperature molten resin between a 1st layer and a 2nd layer, and bonds these together, this embodiment example and the below-mentioned 2nd and 3rd embodiment example As described above, when the first layer has a heat-sensitive recording layer, there is a big problem that the heat-sensitive recording layer is colored by the heat of the molten resin.

In addition, according to the wet laminating method, the application amount of the pseudo-adhesive layer coating solution is smaller than that in the dry laminating method, and thus the time required for drying is short. Therefore, it is excellent in terms of productivity and manufacturing cost, such as enabling mass production at high speed. In addition, when the application amount of the pseudo-adhesive layer coating liquid is small, the second base material layer 16 having a thickness of 5 μm or less can be used, and the pseudo-adhesive layer 19 itself can also be thinned. Heat transfer to the heat-sensitive recording layer 15 and pressure transfer to the pressure-sensitive recording layer 13 are good, and clear recording can be performed. Further, the total thickness of the recording sheet 10A can be reduced, and the recording sheet 10A is suitable for handling as a scroll. Here, if a pseudo-adhesive layer is formed by an extrusion lamination method, the formed layer has a certain thickness. Therefore, the pressure-sensitive recording layer and the heat-sensitive recording layer arranged on the lower layer side than this are used. There is a drawback in that heat transfer and pressure transfer to the layer are poor.

Next, the thermal recording layer 17 is formed by applying and drying a thermal recording layer forming coating solution on the second base material layer 16 of the obtained recording sheet intermediate, thereby forming the thermal recording layer 17 in FIG. Is obtained.
In this case, the thermal recording layer 17 can be formed in the same manner as the thermal recording layer 14 in the first layer 11.

The recording sheet 10A thus obtained can be recorded with characters, images, and the like by being pressurized or heated from the outer surface side of the heat-sensitive recording layer 17 of the second layer 18. Therefore, it can be used effectively as a contract.
For example, a letter indicating the contract contents is thermally printed on a part of the outer surface of the thermal recording layer 17 of the second layer 18 in advance by the thermal printer. At this time, the same sentence is also recorded in the thermosensitive recording layer 15 of the first layer 11.
If Party A and Party B agree to the contents of the contract recorded on the recording sheet 10A,
Signs other than the above-mentioned part on the outer surface of the thermosensitive recording layer 17 of the second layer 18 are each signed with a writing instrument. At this time, since pressure is applied together with writing, the pressure-sensitive recording layer 13 of the first layer 11 is used.
Both signatures will be recorded.
Then, by separating the first layer 11 and the second layer 18 into two sheets by delamination due to cohesive failure in the pseudo-adhesive layer 19, one becomes a contract for storage by the former, and the other is It becomes a contract for storage. Moreover, since this pseudo-adhesion layer 19 cannot be reapplied,
It is also impossible to tamper with the contract by re-bonding the first layer 11 and the second layer 18 together. Therefore, the contract can be made more reliable.

[Second Embodiment]
FIG. 2 shows a recording sheet 10B according to the second embodiment. The positions of the heat-sensitive recording layer 15 and the pressure-sensitive recording layer 13 in the first layer 11 are the same as those of the recording sheet 10A according to the first embodiment. On the contrary, the pressure-sensitive recording layer 13 is disposed so as to contact the pseudo adhesive layer 19.
Further, an intermediate layer 14 is formed between the heat-sensitive recording layer 15 and the pressure-sensitive recording layer 13.
Even in such a recording sheet 10B, the second is the same as the recording sheet 10A of the first embodiment.
By applying pressure or heating from the outer surface side of the heat-sensitive recording layer 17 of the layer 18, it is possible to record characters, images, etc., which can be used effectively as a contract, etc. 1
Since the heat transfer at the time of thermal recording to one thermal recording layer 15 is lower than that of the recording sheet 10A of the first embodiment, it is necessary to make the thermal recording layer 15 of the first layer 11 higher in thermal response. There is.

[Third Embodiment]
FIG. 3 shows a recording sheet 10 </ b> C of the third embodiment, and the first is that the second layer 18 is not provided with a heat-sensitive recording layer and is composed of only the second base material layer 16. This is different from the recording sheet 10A of the embodiment.
When recording is performed on the heat-sensitive recording layer 15 or the pressure-sensitive recording layer 13 of the first layer 11 by heating or pressurizing the recording sheet 10C from the outer surface side of the second base material layer 16. If the second base material layer 16 does not have optical transparency, the content of the recording cannot be visually recognized from the outside at the time of recording, and the first layer 11 and the first layer 11 are separated from the pseudo adhesive layer 19 as a boundary. It is visible only after the two layers 18 are peeled off. Therefore, the third party can be applied as various notices for notifying only certain individuals of non-public personal information, and the contents of notification from the A section of the government office are recorded on one recording sheet 10C. It is also possible to distinguish the contents of notification from Section B, such as pressure sensitive recording.
Moreover, since the pseudo-adhesion layer 19 cannot be re-applied, it is possible to know whether a third person has seen this before a specific individual confirms the notification content.

[Others]
The recording sheet of the present invention has a first base layer, a recording layer capable of pressure-sensitive recording, and a recording layer capable of thermal recording, and further has an intermediate layer between the pressure-sensitive recording layer and the thermal recording layer. As long as the second layer having at least the second base material layer is laminated on the recording layer side of the first layer through the pseudo-adhesive layer by the wet laminating method, the specific configuration is as follows. It is not limited to the three embodiment examples.
For example, the outermost surface of at least one of the recording sheets of each of these examples may be printed with a band shape, a mesh shape, a staggered shape, a spot shape, characters, a background pattern, or the like, or a metal foil or a metal vapor deposition film may be attached. By forming the shielding layer, it is possible to prevent the recorded information from being seen from the outside even when these recording sheets are held over light.
Further, for example, in the third embodiment, by adopting a light transmissive material such as a film substrate such as PET, PP, PE, or a paper substrate such as glassine paper as the second substrate layer. The information recorded on the heat-sensitive recording layer of the first layer may be visible from the outside. In this case, the second base material layer has an effect of protecting the thermosensitive recording layer. In this case, the outer surface of the second base material layer is partially printed with a band shape, a mesh shape, a staggered shape, a spot shape, characters, a background pattern, or the like, or a metal foil or a metal vapor deposition film is pasted. Alternatively, a shielding layer may be formed so that part of the information formed on the heat-sensitive recording layer cannot be viewed from the outside.
Furthermore, in the recording sheet of each of these examples, if necessary, a planned cutting line such as a perforation that penetrates the recording sheet in the thickness direction may be formed at an arbitrary position of the recording sheet, or may be penetrated in the thickness direction. Half-cut processing may be performed, or any character or image for purposes other than shielding may be provided on the outer surface of the first base material layer and / or the second base material layer. .

Furthermore, a layer for the purpose of controlling the degree of adhesion between the layers may be provided between the layers. For example, on one or both sides of the pseudo-adhesion layer, a release agent such as silicon resin or polyethylene wax may be applied to provide a release agent layer so that the first layer and the second layer can be easily separated. An undercoat layer may be provided on one substrate layer or the second substrate layer, and another layer may be formed thereon. In particular, when a known undercoat layer mainly composed of a pigment and an adhesive and conventionally used in heat-sensitive recording materials is formed, the color development sensitivity can be increased when the heat-sensitive recording layer is formed thereon. Examples of the pigment of the undercoat layer exhibiting such an effect include pigments having a high porosity such as silica and calcined kaolin. Further, in the undercoat layer, plastic pigments, hollow particles,
By including a foam or the like, it becomes more effective. Furthermore, the adhesive surface of the first layer or the second layer with the pseudo-adhesive layer is partially provided with a printing portion such as a dot shape or a linear shape in advance, and the formation density of the printing portion is changed to thereby change the adhesive surface. The degree of adhesion between the adhesive layer and the pseudo-adhesive layer may be controlled.
In addition, a known protective layer that has been conventionally used for heat-sensitive recording materials and that mainly contains pigments and adhesives may be formed on the heat-sensitive recording layer.

Further, the back surface of the first base material layer is coated with an adhesive, a rehumidifying adhesive, a delayed tack type adhesive, etc., and the recording sheet of the present invention is applied to the adhesive paper, the rehumidified adhesive paper, the delayed tack paper. Or by forming a magnetically recordable layer (magnetic recording layer) on a part of the back surface of the first base material layer or the surface of the recording sheet to obtain a recording sheet capable of magnetic recording, Higher functions can also be provided.

EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated more concretely, this invention is not limited to these examples. Unless otherwise specified, “parts” and “%” in the examples represent “parts by mass” and “mass%”, respectively.
[Example 1]
The recording sheet of the first embodiment was manufactured as follows.
<Adjustment of thermosensitive coloring component>
(1) Preparation of liquid A (dispersion of leuco dye)
A composition comprising 20 parts of 3-di (n-butyl) amino-6-methyl-7-anilinofluorane, 5 parts of a 5% aqueous solution of methylcellulose and 15 parts of water was averaged in a sand mill.
It grind | pulverized until it became 0 micrometer.
(2) Preparation of B solution (dispersion of developer)
20 parts of bis (3-allyl-4-hydroxyphenyl) sulfone, 5 of methylcellulose
A composition comprising 5 parts of a 5% aqueous solution and 15 parts of water was pulverized with a sand mill until the average particle size was 1.0 μm.
(3) Solution C preparation (dispersion of sensitizer)
20 parts of 1,2-di (3-methylphenoxy) ethane, 5% aqueous solution of methylcellulose 5
A composition comprising 15 parts of water and 15 parts of water was pulverized with a sand mill until the average particle size was 1.0 μm.

<Preparation of coating solution for forming thermal recording layer>
60 parts of a 30% dispersion of silica (trade name: Mizukasil P-527, manufactured by Mizusawa Chemical), Liquid A 2
0 parts, B part 50 parts, C part 10 parts, aqueous dispersion of zinc stearate (trade name: Hydrin Z-
7-30, solid content 31.5%, manufactured by Chukyo Yushi Co., Ltd. 13 parts, SBR latex (trade name: L-
1571, concentration 48%, manufactured by Asahi Kasei Co., Ltd.) 40 parts, and 40 parts of a 10% aqueous solution of silicon-modified polyvinyl alcohol (trade name: R-1130, molecular weight 1700, manufactured by Kuraray Co., Ltd.) are mixed and stirred to form a thermosensitive recording layer. A coating solution was obtained.

<Adjustment of intermediate layer forming coating solution>
Isobutylene / maleic anhydride copolymer ammonium salt (trade name: MCA-2, solid content 3.4%, manufactured by Nippon Kayaku Co., Ltd.) 40 parts, acrylic acid emulsion (trade name: F-300B, solid content 40) %, Manufactured by Nippon Kayaku Co., Ltd.) 59.5 parts, cross-linking agent (trade name: ACL-2, solid content 20%, manufactured by Nippon Kayaku Co., Ltd.) 0.5 parts, mixed with adjusted water, stirred and solidified. A coating solution for forming an intermediate layer having a content of 8% was obtained.

<Preparation of the first layer>
On the pressure-sensitive recording layer of Celcon paper manufactured by Oji Paper Co., Ltd. (KS copy bright, count: N50, color development: blue) in which a self-coloring pressure-sensitive recording layer is formed on the first base material layer, The intermediate layer forming coating solution is applied with a gravure coater so that the coating amount after drying is 1.0 g / m ² and dried to form an intermediate layer, and then the thermal recording layer forming coating solution is A thermosensitive recording layer was formed by coating and drying so that the coating amount after drying with a gravure coater was 4 g / m ² to obtain a first layer. The self-coloring pressure-sensitive recording layer of the cellcon paper used has a single-layer structure, and as the color former, a color former CVL (produced by Yamamoto Chemical Co., Ltd., crystal violet lactone, containing crystal violet lactone in the microcapsule). ) And R-054-K (manufactured by Sanko Chemical Co., Ltd., zinc salicylate) as a developer.

<Formation of recording sheet>
On the first heat-sensitive recording layer, a pseudo-adhesive (trade name: Flutite FB) is used with a gravure coater.
131 (vinyl acetate adhesive), active ingredient 44%, manufactured by Mitsui & Co. Solvent Coat Co., Ltd.) was applied so that the coating amount after drying was 2 g / m ^2, and this pseudo adhesive was not dried. Glassine paper (basis weight 25 g / m ² , density 0.92 g / cm ³ ) is pasted as the second base material layer 16, and then dried, and consists of the first layer / pseudo-adhesive layer / second base material layer. A recording sheet intermediate was obtained.
Next, on the second base material layer of the recording sheet intermediate, the above-mentioned heat-sensitive recording layer forming coating solution was applied with a gravure coater so that the coating amount after drying was 5 g / m ² . This was dried to form a heat-sensitive recording layer, and a recording sheet consisting of the first layer / pseudo-adhesive layer / second layer was obtained.
The adhesive strength according to the T-shaped peeling test method between the first layer and the second layer in the obtained recording sheet was 180 mN / 25 mm (peeling speed 300 mm / min).

[Example 2]
In the preparation of the intermediate layer forming coating solution, MCA-2 was changed to 15 parts and F-300B was changed to 84.5 parts. In the production of the first layer, the intermediate layer forming coating solution was dried with a gravure coater. A recording sheet of Example 2 was obtained in the same manner as in Example 1 except that the coating amount was 2.0 g / m ² and the coating sheet was dried.

[Comparative Example 1]
In the production of the first layer, a recording sheet of Comparative Example 1 was obtained in the same manner as in Example 1 except that the intermediate layer was not formed.

[Comparative Example 2]
In the preparation of the intermediate layer forming coating liquid, MCA-2 was 5.0 parts and F-300B was 94.5 parts. In the production of the first layer, the intermediate layer forming coating liquid was dried with a gravure coater. A recording sheet of Comparative Example 2 was obtained in the same manner as in Example 1 except that the coating amount was 2.0 g / m ² and the coating sheet was dried.

[Comparative Example 3]
In the preparation of the intermediate layer forming coating solution, 100 parts of F-300B was used, and in the production of the first layer, the coating amount after drying the intermediate layer forming coating solution with a gravure coater was 3.0 g / m ² . A recording sheet of Comparative Example 3 was obtained in the same manner as in Example 1 except that coating and drying were performed.

The recording sheet thus obtained was subjected to the following evaluation test, and the results obtained are shown in Table 1.

[Thermal recording density]
Using a thermal evaluation machine [trade name: TH-PMD, manufactured by Okura Electric Co., Ltd.], each recording sheet was recorded at an applied energy of 0.75 mJ / dot, and the recording density of the thermal recording part was measured using a Macbeth densitometer [RD-914 type]. , Manufactured by Macbeth Co., Ltd.] in the visual mode.

(Pressure sensitive recording density)
Two recording sheets after the above thermal recording are stacked so that the recording layer surface is on top, and recorded with a pressure-sensitive printing evaluation machine [trade name: VP-1850, manufactured by Epson Corporation], and the recording density of the pressure-sensitive recording section is set to Macbeth. It measured with the blue filter with the densitometer [RD-914 type | mold, the Macbeth company make].

[Reduced pressure-sensitive recording density]
The recording sheet used above was allowed to stand for 7 days at 23 ° C. and 50% RH, and then measured with a Macbeth densitometer using a blue filter.

[Skin dirt]
The recording sheet is taken up and left at room temperature for 7 days, and then the whiteness of the recording layer surface (based on JIS P 8123) is measured to represent background stains. The larger the value (%), the better the background dirt.

  The recording sheets obtained in each example did not have a decrease in pressure-sensitive recording density, were excellent in background stains during winding, and the printing on each recording layer was clear. On the other hand, the recording sheets obtained in the respective comparative examples were inferior to the background stains on winding.

It is sectional drawing of the recording sheet of the example of 1st Embodiment. It is sectional drawing of the recording sheet of the example of 2nd Embodiment. It is sectional drawing of the recording sheet of the example of 3rd Embodiment.

Explanation of symbols

10A to 10C Recording sheet 11 First layer 12 First substrate layer 13 Pressure sensitive recording layer 14 Intermediate layer 15, 17 Thermal recording layer 16 Second substrate layer 18 Second layer 19 Pseudo-adhesive layer

Claims (4)

A first base layer comprising a first base layer, a pressure sensitive recording layer capable of pressure sensitive recording, an intermediate layer, and a thermosensitive recording layer capable of thermal recording; and a second layer comprising at least a second base material layer. And the second layer is a recording sheet laminated on the recording layer side of the first layer via a pseudo-adhesion layer, wherein the pseudo-adhesion layer is formed by a wet lamination method Recording sheet.   2. The recording sheet according to claim 1, wherein the intermediate layer contains an alkali salt of an isobutylene / maleic anhydride copolymer. The recording sheet according to claim 1, wherein the pressure-sensitive recording layer is a self-coloring pressure-sensitive recording layer containing a color former and a developer.   The recording sheet according to claim 1, wherein the second layer further includes a thermosensitive recording layer.

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